1. Field of the Invention
The present invention is in the field of data processing, and more specifically relates to a keyboard for data entry. The keyboard of the present invention converts the actuation of its various keys to electrical signals; it is not a part of any particular machine. However, it can be electrically connected to a typewriter, word processor, printer, computer or other device so that its electrical signals can be utilized to control the operation of such other devices.
2. The Prior Art
A detailed discussion of the prior art is contained in a Prior Art Statement that has been lodged in the Patent Office file of this application. Accordingly, only an abbreviated discussion will be presented here.
In one aspect of the present invention, the SHIFT key assigns alternative characters to only the character keys and not to the punctuation keys. In the prior art, it was common for the SHIFT key to affect all of the keys on the keyboard and to assign alternative characters to the punctuation keys.
Typically, the punctuation keys are located at some distance from the home keys, and most users find it difficult to strike the desired punctuation key with confidence. The present inventor recognized that the location of the punctuation keys imposes a burden on the user and that this burden should not be increased by adding the complication that the punctuation key has two alternative characters. In the present invention, each punctuation key includes only one character which remains unchanged regardless which mode the keyboard is in.
In another aspect of the invention, palm pads are provided and they serve both as hand rests and as operational keys. Two types of hand rest are known in the prior art. One kind is simply an actuator which is not intended to support a substantial part of the weight of the hand, but instead is pushed by the hand to effect some function. Another type of hand rest known in the prior art serves only to space the fingers from the proximity-actuated keys to avoid accidentally operating the keys. None of the hand rests found in the prior art are specifically shaped and contoured to fit the shape of the hand of the user, as is the case in the present invention.
In another aspect of the present invention, special keys are provided for the purpose of selectively altering the location of the writing position or cursor. These four keys are used respectively for controlling the motion of the cursor or writing position relative to the medium in the four directions: left, right, up, and down. Each of these keys is slidable in the direction that the key controls. No comparable cursor control system is known in the art.
In a fourth aspect of the invention, the palm pads that also serve as hand rests are used for operating the SHIFT. One earlier patent shows a shift key located under the palm of the left hand, but it is not usable by both hands and includes no provision for shift lock.
In a fifth aspect of the present invention a system of chording is used to input the 26 different characters of the English alphabet. Although chording has been used in some prior art keyboards, the particular scheme of chording used in the present invention is thought to be unique.
Thus, it appears that the present invention has a number of novel features which are not disclosed in the prior art. In the following section, these features will be discussed in greater detail.